* Oil Type: 5W-30 is a very common and likely the best starting point for a 1999 Mustang V6. Your owner's manual will confirm this. Sometimes a 10W-30 is acceptable, particularly in warmer climates, but 5W-30 offers better cold-weather protection.
* Oil Certification: Look for an oil that meets the specifications listed in your owner's manual. Common certifications include:
* API: Look for an API certification symbol (like "SN" or a newer designation - check your manual). This indicates the oil meets certain performance standards.
* Ford WSS-M2C913-A/B/C/D/E: This is a specific Ford certification, and finding an oil that meets it is crucial for optimal engine performance and longevity. Again, check your owner's manual for the *exact* specification.
Where to find the correct information:
The most reliable source is your 1999 Ford Mustang owner's manual. It will specify the exact recommended oil type, viscosity, and certifications. Failing that, you can:
* Check online Ford resources: Search Ford's website for your vehicle's specifications.
* Consult a mechanic: A qualified mechanic will be able to tell you the correct oil for your specific Mustang.
Using the wrong oil can damage your engine, so it's critical to get this right. Don't rely solely on general advice; always consult your owner's manual first.
